/**
 * 账户每四位数字加上空格.
 * @param {*} val 账号 6666111122228888
 * @returns  6666 1111  2222  888
 */
export function account4Space(val) {
    if (!val) return val;
    if (val.length <= 4) return val;
    const size = val.length;
    let lastStr = '';
    for (var inx = 0; inx < size; inx++) {
        if (inx !== 0 && inx % 4 === 0) {
            lastStr += ' ';
        }
        lastStr += val.charAt(inx);
    }
    return lastStr;
}
